Find Largest Value in Each Tree Row - LeetCode
Solution
class Solution {
func largestValues(_ root: TreeNode?) -> [Int] {
var dict = [Int: [Int]]()
traversing(root, 0, &dict)
var result = [Int]()
for key in dict.keys.sorted() {
result.append(dict[key]!.max()!)
}
return result
}
func traversing(_ root: TreeNode?, _ deep: Int, _ dict: inout [Int: [Int]]) {
guard let root = root else {
return
}
if let array = dict[deep] {
dict[deep] = array + [root.val]
} else {
dict[deep] = [root.val]
}
traversing(root.left, deep + 1, &dict)
traversing(root.right, deep + 1, &dict)
}
}
